Device for calculating horse-power.



No. 809,019. PATENTED JAN. 2, 1900. E. M00. SGOVILLE.

DEVICE FOR CALCULATING HORSE POWER.

APPLIGATION FILED JAN.31, 1905.

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A TTORMEYS UNITED STATES PATENT OFFICE.

EUGENE MOCLELLAN SCOVILLE, OF IVAIPAH U, TERRITORY OF HAIVAII.

DEVICE FOR CALCULATING HORSE-POWER.

Specification of Letters Patent.

Patented Jan. 2, 1906.

Application filed January 81, 1905. Serial No. 248,497.

To M111 whont it Wtcty concern:

Be it known that I, EUGENE MGULELLAN SoovILLE, a citizen of the UnitedStates, and a resident of VVaipahu, Oahu, Territory of Hawaii, haveinvented a new and Improved Device for Calculating Horse-Power, of whichthe following is a full, clear, and eXact description.

My invention relates to a planimeter, in combination with a supporttherefor especially adapted for the operation of the planimeter andprovided with a new and improved sliderule particularly designed forcalculating horse-power.

The principal object of my invention is to provide means for calculatinghorse-power from an indicator-card accurately, conveniently, andrapidly.

Further objects of the invention are to pro- Vide a portable support fora planimeter having a surface for supporting the moving parts thereofand also for holding the indicatorcard and the slide-rule, to provide aplanimeter of improved construction, perfectly balanced and capable ofbeing readily set in position to be operated, and also to provide aslide-rule which, while capable of being operated like an ordinaryslide-rule, can be used for computing horse-power from mean eifectivepressure and other necessary data with but two settings.

Reference is to be had to the accompanying drawings, forming a part ofthis specification, in which similar characters of reference indicatecorresponding parts in all the figures.

Figure l is a plan showing a preferred form of my invention. Fig. 2 isan end elevation thereof, partly in section. Fig. 3 is a sectional viewof a preferred form of planimeter constituting a portion of myinvention, showing parts in section; and Fig. 1 is a rear view of aportion of the slide-rule.

A base or support 10 is provided with a iiat surface adaptedv to receivethe moving parts of a planimeter and to afford a proper surface for themto operate upon. Secured about in the middle of this surface on thesupport is an anchor-plate 11, having a longitudinal slot 12. This slotis adapted to receive a projection 13 upon a carriage 14. Thisprojection is provided with a central point or indicator 13. Thecarriage is provided with a rod 15, upon which is adjustably mounted atracing-point 16. This tracing-point is mounted in a bearing 16 and issecured in adjusted positions by a thumb-screw 16 The body of theplanimeter, which has heretofore been designated as a carriage, isprovided with a pair of springs 17. These springs are adapted to engagea movable shaft or rod 18 and are provided with bearings 19 for thatpurpose. The shaft 18 is adapted to move longitudinally and rotate inthese bearings. Upon one end of the shaft is asmooth-surfaced wheel 20of enough weight to balance the device and to serve as a balance-wheelfor it. Upon the other end the shaft is provided with a wheel 21, havinga sharpened edge for engaging the surface upon which the Wheels roll andpreventing the longitudinal motion of the shaft except by the rotationof the wheel upon its sharpened edge. The shaft is provided with anindicatingmark 22, adapted to show upon a scale 23, held by the springs17, the mean effective pressure represented by the indicator-cardoperated upon. The support is provided with clips 24 for securing theindicator-card 25 thereto.

Upon one side of the support three scales A, D, and E are provided Thefirst of these scales is divided so as to represent mean ef fectivepressures, as is indicated on the drawings by the letters M. E. P. It isalso provided with the letters H. P. at the top for an obvious purpose.The scale E indicates diameters of the cylinder and is so designated.Between the scales A and D is located a groove 26, in which fits a slide27. On one end of the slide it is provided with divisions or graduationsrepresenting the stroke, as is indicated at the bottom in the drawings,and upon the other end the graduations represent revolutions per minute,as is indicated at the top. This slide is capable of movinglongitudinally in the groove 26. The slide is also provided with alongitudinal groove 28, in which is mounted a rider 29. This rider isprovided with an indicating-mark 30, and the scale Eis provided with agage-point 31, the purpose of which will be explained. This gage-pointis preferably located at a point indicating twenty-two and one-half onthe scale E. 26, but being mounted thereon will move with it when theslide is moved. The slidefiule can, as usual, be provided with a gage32. The rear of the slide 27 is provided with gradations, as shown inFig. 4:, similar to those of the standard Mannheim scale, so that byremovingthe rider 29 and inverting the slide the slide-rule can be usedin the ordinary manner.

The rider can be moved along the slide ;matical calculations.

It is to be understood that the principal object to be attained by thisinvention is the complete calculation of the horse-power from theindicator-card and other data known by any person whether skilled inmathematics or not and without the employment of any mathe- Themanipulation of the slide-rule is effected by only two settings, Which,it is believed, has not heretofore been accomplished.

The operation of the embodiment of the in vention which is illustratedin these drawings will now be described. The indicator-card 25 is placedunder the clips 24 in an obvious manner. A scale 23, corresponding tothe inclicator-spring, is placed on the planimeter under the springs 17.The points 13 and 16 are then set to the extreme length of the diagramon the indicator-card and the thumb-screw 16" tightened. The planimeteris then placed in position with its fulcrum-pin 13 in the slot 12. Themark 22 on the axle or shaft is set to Zero on the scale 23. The paperis preferably pricked to show the starting-point of the tracing-pin, andthe diagram is traced in a righthand direction until the starting pointis reached. The indicating-mark 22 will then indicate the mean effectivepressure directly upon the scale 23. By setting the points 13 and 16 sixinches apart and using a scale having sixty divisions to the inch areasin square inches can be directly computed on the planimeter instead ofmean effective pressure. After obtaining the mean effective pressurewith the planimeter the slide 27 of the rule should be so set that thestroke in inches as represented on the lower half of the slide isopposite the calculated mean efiective pressure upon the scale A. Therider 29 is then moved along the slide until its indicating-mark 30coincides with the gage-point 31, the slide of course remainingstationary during this adjustment. The slide is then moved, carrying therider until the latter is opposite the cylinder-diameter in inches onthe scale E. Then on the scale A, opposite the revolutions per minute asrepresented upon the upper half of the slide, thehorse-power can bedirectly read. If in extreme cases the reading isolf the board, therider can be set to half the cylinder diameter and theresu lt multipliedby four. As an example, taking an engine twenty by forty-two, M. E. P.seventy-five pounds, R. P. M. sixty, set the point 4.2 on the slide to75 on the lower scale A. Then without moving the slide set the rider tothe gage-point on the scale E. Then move the slide carrying the riderwith it until the indicating-mark on the rider coincides with thenumeral 20 on the scale E, and on the scale A opposite the reading onthe upper part of the slide read the resultnamely, three hundredhorse-power.

1 If the diameter of the cylinder for any desired horse-power isrequired, set the stroke to the M. E. 1 set the marker to the gage-point31, set the revolutions to the horse-power deameter on the scale E. Itwill be noticed that the scale D is notemployed in these calculations;but it is retained because upon inverting the slide a regular slide-rulecan be obtained.

iVhile I have illustrated and described a particular embodiment of myinvention, itwill be readily understood that the latter is not limitedto that embodiment, but may be constructed in many other forms, and thatmany from the spirit of the invention.

Having thus deseri bed my invention, 1 claim as new and desire to secureby Letters Patent 1. A calculating device comprising a pair of scales,one being provided with a stationary gage-point, and a slide having ascale adapted to register with one of the first-mentioned scales andprovided with a rider slidably mounted thereon and adapted to registerwith the other stationary scale and with the gagepoint.

2. The combination with a support,o'l. a sliderule thereon having twostationary scales, and a slide provided with a s ale and with a riderslidably mounted thereon and adapted to register with one of saidstationary scales.

3. A calculating device, comprising a pair of scales, one representingmean efl'ective p ressures in horse-powers, and the other representingcylinder diameters, the second scale being provided with a stationarygage-point, a slide having a scale adapted to register with thefirst-mentioned scale and provided with a rider slidabl y mountedthereon and adapted to register with the second stationary scale andwith the gage-point.

A. A device for calculating horse-powers, comprising a stationary scalehaving divisions representing mean eflective pressures and horse-powers,a second stationary scale having divisions representing cylinderdiameters and a gage-point among said divisions, and a slide adapted tomove along both of said firstmentioned scales and provided with a scalerepresenting revolutions per minute and length of stroke and having arider slidably mounted thereon adapted to register with the second ofsaid stationary scales and with said gage-point.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

EUGENE EUC'IJELI'IAN SCOVlhhE.

Vitnesses:

F. B. ns'r, F. l/V. MAnNIImn.

sired, and opposite the marker read the dimodifications may be madewithout departing

